1. Field of the Invention
The invention is directed to a device for producing a tube, in particular a tube-shaped printing form, with a continuous circumferential surface, from a plate with a register hole system.
2. Discussion of the Prior Art
The prior German Patent Application P 41 40 768 discloses a tube-shaped offset printing form which has a continuous circumferential surface without gaps and can be slid onto a form cylinder and positioned thereon in a working position in a frictionally locking manner and in correct register. The tube is produced from a commercially available printing plate of metallic work material which is cut to size. The beginning and end edges of the plate are connected, e.g. welded, with one another in such a way that the tube has an uninterrupted circumferential surface with the exception of the connecting seam. In addition, the printing plate is provided with a register hole system so that it can be clamped in a welding device in the correct position and seam-welded along its length.
The clamping of the plate in the correct position and the forming of the plate into a tube were formerly carried out by cumbersome manual labor. There is no known device in which it is required only that the cut plate be inserted and in which the curving or rolling process and positioning of the ends of the plate in exact register are achieved for the connection after the insertion of the plate.